Mounting socket



J 2- A. s. MUELLER 2,290,701

MOUNTING SOCKETv Filed D60. 16, 1941 In vent or".

Adolf G. Mueller",

Patented July 21, 1942 MOUNTING SOCKET Adolf G. Mueller, Fairi'ield, Coma, assignor to General Electric flompany, a corporation of New York Application December 16, 1941, Serial No. 423,171

OFFICE 2 Claims. (or. 173-328) My invention relates to mounting sockets and more particularly to a mounting socket for a starting mechanism commonly employed with a fluorescent lamp of the well known type now in commercial use.

An object of my invention is to provide an improved mounting socket of the type described so constructed that the starting mechanism may be readily connected and disconnected therefrom and which permits mounting the starting mechanism at a point adjacent the fluorescent lamp.

Another object of my invention is the provision of a mounting socket for a starting mechanism which comprises relatively few parts and which may be easily assembled and manufactured at low cost.

In the accompanying drawing, Fig. 1 is a view of a fluorescent lamp and associated starting mechanism mounted in a socket constructed in' accordance with my invention;- Fig. 2 is a view of the starting mechanism mounted in the socket; Fig. 3 is a plan view of the socket taken along lines 3-3 of Fig. 2; Fig. 4 is a view of the interior of the socket, and Fig. 5 is an exploded view of the elements of the mounting socket.

Referring to the drawing, Fig. 1 illustrates an electric discharge device H), such as a fluorescent lamp, supported at each end on sockets II, the sockets themselves being supported on a mounting strip or reflector base I2 of a lamp fixture, or the like. This is one of the ways commonly employed in mounting a fluorescent lamp in fixtures for use in a wide variety of installations. Fluorescent lamps of the type mentioned require a starting switch for applying current to the cathodes of the lamp to heat them to a point at which they become emissive; the lamps also require an impedance, such as a reactor, to limit the current flow through the cathodes. Once the .cathodes are heated, a discharge are is struck between them lighting the lamp and shorting out the switch.

' It is advantageous to mount the starting switch at a point where it is easily accessible for installation or replacement because in some cases, it has been found that failure of a fluorescent lighting system is due to failure of the starting switch. Failure of the reactor rarely, if ever, oc curs since it is constructed of relatively rugged material and seldom needs attention. If provision is made for easy replacement of the starting switch, it is possible to take care of most instances wherein shut-down of the lamp is due to failure of the starting system. I

To this end, I provide a mounting socket {3 to receive a starting switch mechanism H. These elements are constructed with coacting contact means so designed that the starting mechanism may be easily connected and disconnected from the socket l3. Removal of the switch mechanism is accomplished simply by grasping it in the hand and turning it within the socket member. The socket i3 may be mounted at any convenient point, preferably adjacent the fluorescent lamp. By way of example, it has been shown mounted below the reflector surface l2. The starting switch maybe any of the well known types now on the market, such as the thermal or glow discharge type. As shown by Fig. 5, the switch proper is disposed within a container l5 provided with spaced contact pins i6 having enlarged heads H for making an electrical connection with the socket. The contact pins it provide the means for mounting and supporting the starting mechanism within the socket |3 as well as providing a means for maintaining an electrical connection with the starter switch..

The socket l3 comprises two spaced parallel plates of insulating material, for example, sheet fiber. The upper plate It is provided with two arcuate keyhole slots I9 for-receiving the contact pins I8 of the starting switch while the lower plate 20 covers the openings formed by the keyhole slots and insulates the ends of the contact pins as they are seated in the upper plate. In mounting the starting switch on the socket, the enlarged heads ll of the starter contact pins are inserted through the large portions of the keyhole slots and then the container i5 is rotated to move the contact pins to a position such that the narrower portions of the contact pins are seated in the corresponding narrower portions of the keyhole slots with the heads ll disposed beneath the slots in the space formed between the plates l9 and 20. This means that the en-' larged heads of the contact pins are locked beneath the narrower portions of the keyhole slots so that the container cannot be pulled out of the socket.

Cooperating with the contact pins are spaced flexible contact members 2!. These contact members are disposed in the space between the upper and lower plates at points adjacent the keyhole slots so that as the contact pins in the starting switch are rotated within the keyhole slots, they engage the contact members. Each contact member is provided with an integrally formed terminal lug 22 which flts within a slot 23 formed in the lower plate so that it extends beneath the plate, as shown by Fig. 2, for connection to the conductors of the lamp operating circuit. 'That portion of the contact member adjacent the terminal lug 22 is curved outwardly, as shown at 24. This means that in assembled position, it is spaced from the wall of the keyhole slot so that as the contact pin oi the starting switch is inserted in the keyhole slot, it will not immediately engage the contact member. In order to engage the contact pin, however, the contact member is provided with an indented or projecting portion 25 which, when the contact is in assembled position, extends into the plane of the keyhole slot at a point adjacent the narrower portion of the slot so that as the starter pin is turned in the keyhole slot, it will engage the projection 25 causing the contact member to be defiected outwardly. This permits the starter pin to snap past the projection into seated position in the narrower portion of the keyhole slot. In this position, the enlarged head I] of the contact pin engages a curved portion 28 on the contact member and is held in position by projection 25, as shown in Fig. 3.

At the end opposite that on which the lug 22 is formed, the contact member is provided with an integral tang 21 which is disposed in a recess 28 formed in the lower plate 20. It should be noted that the recess 28 is of suflicient width to permit movement of the tang 21 therein sumcient to provide for ilexure of the contact member as the switch contact pins are snapped into position. The cooperating tang and slot provide a guide means for the movable end of the contact member. The contact member is normally biased into engagement with an edge 29 ofthe slot 28 so that it is at all times positioned correctly with respect to the keyhole slot.

It will be apparent from Fig. 5 that both of the contact members 2| are constructed exactly alike and that they are assembled in.the socket simply by placing the lug 22 and the tang 21 in the corresponding slot 23 and recess 28. Thereafter, the upper plate It is assembled on the lower plate 20 so that the contact members are held securely in position. The upper and lower plates are held together in any suitable manner punched from sheet insulating material. The contacts are simply set in the slots in the lower plate. and held in position by the upper plate;

combination, a plate of insulating material havas by hollow rivets 30 which extend through openings 3| in each of the four corners of the. plates. Spacer washers 32 are mounted on each of the rivets between the plates to maintain them in properly spaced position. The hollow rivets provide a simple mounting means for the socket since bolts may be passed through the rivets to fasten the socket to a support, as shown at 33 in Fig. 1.

My mounting socket is one which may be easily assembled and manufactured at low cost. To this end, the supporting plates l8 and 20 may be ing spaced slots and recesses therein, a pair or contact members, each contact member comprising a strip of flexible material having adjacent projecting and curved portions, each contact member being provided at one end with a terminal lug seated in a corresponding slot and a tang at the other end seated in a corresponding recess, a second plate of insulating mate al overlying said first-mentioned plate and be g provided with arcuate keyhole slots, the o- 'jecting portions of the contact members exte ding into the planes of the keyhole slots at the beginning of the narrower portions of the slots. the contact prongs or the electrical device being inserted through the wider portions of said keyhole slots and snapped past the projecting portions of the contact members into seated position in the narrower portions of the slots in eleo- .ing. spaced slots and recesses therein, a pair of contact members, each contact member comprising a strip or flexible material having a projecting portion, each contact member also being provided at one end with a terminal lug seated in a corresponding slot and a tang at the other end seated in a corresponding recess, a second plate of insulating material overlying the said firstmentioned plate and being provided with keyhole slots, the contact members being positioned between said plates with the projecting portions of the contact members extending into the planes of the keyhole slots whereby the contact prongs of the electrical device may be inserted in said keyhole slots and snapped past the projecting portions of the contact members into seated position in the slots in electrical engagement with the contact members and means for fastening said plates together.

ADOLF G. MUELLER. 

